Pull-based Log-transfer Replication System

Replication is important in distributed environment. Replication provides users with their own local copies of data. These local, updatable data copies can support increased localized processing, reduced network traffic and easy scalability. However, the major disadvantage of replication is that when a given replicated object is updated, all copies of that object must be updated: the update propagation problem. The pull-based log-transfer replication system allows replica contents to become stale but in a controlled way. This system will become more efficient and available than traditional replication systems that keep all the replicas consistent, especially when the network and computers are unreliable. Therefore, this system makes to reduce the update propagation in the pull-based single master optimistic replication system by using the log